The number 18501
18501 is a composite number with 8 divisors. Its prime factorisation is 3 × 7 × 881. Divisors (8): 1, 3, 7, 21, 881, 2643, 6167, 18501.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 18501: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
18501 is composite. Its prime factorisation is
- 3
The divisors add up to 28224; without 18501 itself that is 9723, so 18501 is deficient (9723 is less than 18501). Euler's totient φ(18501) = 10560 numbers up to 18501 share no factor with it.
- 4
The digits of 18501 add up to 15, and repeating that until one digit is left gives the digital root 6. The Collatz sequence (halve if even, else 3n+1) takes 35 steps to reach 1.
LaTeX source of the formulas on this page
\[ 18501 = 3 \times 7 \times 881 \]
18501 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 28224 |
| Euler totient φ(n) | 10560 |
| Square | 342287001 |
| Cube | 6332651805501 |
| Square root | 136.018381 |
| Digit sum / digital root | 15 / 6 |
| Collatz steps to 1 | 35 |
| Scientific notation | 1.8501 × |
18501 in other forms
| Form | Value |
|---|---|
| In words | eighteen thousand five hundred and one |
| Binary (base 2) | 100100001000101 |
| Octal (base 8) | 44105 |
| Hexadecimal (base 16) | 4845 |
| Base 3 | 221101020 |
| As time | 18501 seconds = 5 h 8 min 21 s |
Is 18501 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | No (remainder 1) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (18501 ÷ 3 = 6167) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 1) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 1) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | No (remainder 3) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | Yes (18501 ÷ 7 = 2643) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | No (remainder 5) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 6) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 1) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 10) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 9) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 18501 a prime number?
No. 18501 = 3 × 7 × 881, so it is divisible by 3.
What are the factors of 18501?
1, 3, 7, 21, 881, 2643, 6167, 18501.
What is 18501 in binary?
100100001000101 (hexadecimal 4845, octal 44105).
What is the square root of 18501?
About 136.0184.
Is 18501 divisible by 3?
Yes. Its digits add up to 15, a multiple of 3.
What is special about the number 18501?
18501 is a happy number: repeatedly adding the squares of its digits reaches 1.